Zanzo opened this issue on Aug 11, 2009 · 95 posts
pjz99 posted Tue, 11 August 2009 at 4:21 PM
and for reference, another "room" box is included, "Room Outer", with the normals facing out. With both the IBL and the environment sphere, it occludes all incoming light (which imo shows again that including normal facing in GI calculations is not a good idea, it shouldn't matter).
Edit: to clarify, it doesn't work like either of us thought it did; with an IBL that has shadows turned off, light passes in through the backfacing normals; with the environment sphere, it is occluded. With outward-facing normals, both are occluded.